add pop3 daemon

https://github.com/fphammerle/docker-dovecot/issues/19
https://git.alpinelinux.org/aports/commit/main/dovecot?id=e02aad8c475a7413777e720103c1694f0d5e8487

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- pop3 daemon
 
 ## [1.2.0] - 2020-03-12
 ### Added

Dockerfile

@@ -5,6 +5,7 @@ ARG SOCAT_PACKAGE_VERSION=1.7.4.2-r0
 RUN apk add --no-cache \
         dovecot-lmtpd=$DOVECOT_PACKAGE_VERSION \
         dovecot-pigeonhole-plugin=$DOVECOT_PACKAGE_VERSION \
+        dovecot-pop3d=$DOVECOT_PACKAGE_VERSION \
         dovecot=$DOVECOT_PACKAGE_VERSION \
         socat=$SOCAT_PACKAGE_VERSION \
     && find /etc/ssl/dovecot -type f -print -delete